With the rapid development of the automobile industry, the number of the fuel vehicles is growing. Although the standards of automobile emissions have been made, the pollution caused by the emissions can not be prevented completely.
At present, batteries, especially high power batteries, are playing a very important role in the hybrid vehicles (HEV), pure electric vehicles (EV) and other electric devices. As people have growing requirements for the environment, hybrid vehicles (HEV) and pure electric vehicles (EV) will be the future developing direction. Hybrid vehicles (HEV) and pure electric vehicles (EV) usually employ a battery pack as a power supply to drive the motor. The design of a battery pack should meet many requirements. For example, the basic battery performance should meet the requirements for driving a vehicle. Furthermore, the housing of the battery assembly should have a structure compatible with the vehicle.
As FIG. 1 shows, CN2679860Y disclosed a rectangular lithium ion battery pack. The battery pack comprises a battery body (1) and a battery fastening device (2). The battery body (1) comprises a multi-cell assembly. Each cell comprises a positive and a negative terminal. The positive and negative terminals of the cells are connected in series. The battery fastening device (2) comprises two pressing plates (3) and a plurality of connecting strips (4). The two pressing plates (3) are placed in the two ends of the battery body (1), respectively. The two pressing plates press the battery body (1). The connecting strips (4) are connected to the two pressing plates (3) and fasten the battery body (1).